package servlet.content.util;

import java.io.IOException;
import java.io.PrintWriter;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Iterator;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import offer.GetDataSource;
import offer.GetItemsObject;
import offer.GetNodeFromModule;

import com.netscenery.yang.model.*;

public class AjaxGetDerivedTypeServlet extends HttpServlet {

	/**
	 * Constructor of the object.
	 */
	public AjaxGetDerivedTypeServlet() {
		super();
	}

	/**
	 * Destruction of the servlet. <br>
	 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	/**
	 * The doGet method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to get.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		response.setContentType("text/html");
		PrintWriter out = response.getWriter();
		out
				.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
		out.println("<HTML>");
		out.println("  <HEAD><TITLE>A Servlet</TITLE></HEAD>");
		out.println("  <BODY>");
		out.print("    This is ");
		out.print(this.getClass());
		out.println(", using the GET method");
		out.println("  </BODY>");
		out.println("</HTML>");
		out.flush();
		out.close();
	}

	/**
	 * The doPost method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to post.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		response.setContentType("text/xml; chartset = utf-8;");
		request.setCharacterEncoding("utf-8");
		response.setHeader("Cache-Control","no-cache"); 
		PrintWriter out = response.getWriter();
		String       baseTypeStr  = request.getParameter("baseType");
		String       nodeLevel    = request.getParameter("nodeLevel");   //ͨ������������ҽ��
		String[]     levels       =  nodeLevel.split("\\\\");
		//������Դ
		Module       module       = GetDataSource.getDataRead(request);
		Leaf         leaf         = (Leaf)GetNodeFromModule.getDataDefByLervels(module, levels);
		
		Type tempType = null;
		//****************************************************************************//
		//��leafΪnullʱ����nodeLevel����Typedef��Unionҳ��
		if(null == leaf){
			ModelElement element = GetNodeFromModule.getModuleElement(module, levels);
			if(element instanceof Type){
				tempType       = (Type)element;
			}else if(element instanceof Deviate){
				//����deviate��Type
				Deviate deviate = (Deviate)element;
				tempType  = deviate.getType();
				if(null == tempType){
					tempType = deviate.createType(baseTypeStr, null);
				}
			}
		}else{
			tempType = leaf.createType(baseTypeStr, null);
		}
		//****************************************************************************//
		if(null == tempType){
			return;
		}

		Env env = null;
		Method getEnv = null;
		if(null == leaf){
			getEnv = GetItemsObject.getMethod(tempType, "newSubEnv");
		}else{
			getEnv = GetItemsObject.getMethod(leaf, "newSubEnv");
		}
//		getEnv = GetItemsObject.getMethod(leaf, "newSubEnv");
		getEnv.setAccessible(true);
		try {
			env = (Env)getEnv.invoke(tempType);
		} catch (IllegalAccessException e) {
			e.printStackTrace();
		} catch (IllegalArgumentException e) {
			e.printStackTrace();
		} catch (InvocationTargetException e) {
			e.printStackTrace();
		}
		//ArrayList<String> derivedTypeList = new ArrayList<String>();
		ArrayList<String> derivedTypeList = Type.getAvailableDerivedTypes(env , baseTypeStr);
		
		StringBuilder     xmlData         = new StringBuilder();
		
		xmlData.append("<?xml version='1.0' encoding='UTF-8'?>");
		xmlData.append("<derivedList>");
		//����Ӧ��derived����Ϊ�գ��򷵻ؿ�
		if(null == derivedTypeList || derivedTypeList.size() ==0){
		}else{
			Iterator<String>  iterator        = derivedTypeList.iterator();
			while(iterator.hasNext()){
				xmlData.append("<derivedItem>"+iterator.next()+"</derivedItem>");
			}
		}
		xmlData.append("</derivedList>");
		out.write(xmlData.toString());
		out.flush();
		out.close();
	}

	/**
	 * Initialization of the servlet. <br>
	 *
	 * @throws ServletException if an error occurs
	 */
	public void init() throws ServletException {
		// Put your code here
	}

}
